Dewatering system

Abstract

A system for processing drilling mud, the system including a primary separation tank having an inlet for receiving drilling waste and an outlet in fluid communication with a feed line, and an injection pump in fluid communication with a polymer tank and the feed line. The system also includes a clarifying tank in fluid communication with the feed line and a first collection tank, wherein effluent from the clarifying tank is discharged into the first collection tank, and a centrifuge in fluid communication with the clarifying tank and a second collection tank, wherein effluent from the centrifuge is discharged into the second collection tank.

What is claimed is: 
     
       1. A system comprising:
 a primary separation tank having an inlet for receiving drilling waste and an outlet; 
 an injection pump in fluid communication with the outlet of the primary separation tank and a polymer tank; 
 a clarifying tank having a venturi zone formed adjacent to an outlet of a constricted pipe coupled to a first end of an internal pipe, wherein the internal pipe has a total length defined between the first end of the internal pipe and a second end of the internal pipe located opposite with respect to the first end, wherein the venturi zone is located inside the internal pipe adjacent to the first end of the internal pipe and, at least partially, located below the outlet of the constricted pipe between the first and second ends of the internal pipe, wherein at least a portion of the constricted pipe is disposed within the clarifying tank and the constricted pipe is in fluid communication with the outlet of the primary separation tank and the injection pump, and wherein the clarifying tank is fluidly coupled to a first collection tank, the clarifying tank further comprising a settling zone adjacent to the second end of the internal pipe and in communication with the internal pipe to receive particulates from the drilling waste that passes through the venturi zone adjacent to the first end of the internal pipe and from the second end of the internal pipe; 
 a centrifuge in fluid communication with the clarifying tank and a second collection tank; and 
 a centrifugal pump to pump fines and effluent from the clarifying tank to the centrifuge. 
 
     
     
       2. The system of  claim 1 , wherein the primary separation tank is a tank of a sand trap. 
     
     
       3. The system of  claim 1 , wherein the polymer tank comprises a dual tank. 
     
     
       4. The system of  claim 1 , wherein the first collection tank comprises a back flow line in fluid communication with the primary separation tank. 
     
     
       5. The system of  claim 1 , wherein the polymer tank is in fluid communication with at least one polymer injection pump. 
     
     
       6. The system of  claim 1 , wherein the injection pump comprises a polyductor configured to mix a polymer into the drilling waste. 
     
     
       7. The system of  claim 1 , wherein the second collection tank is in fluid communication with an active drilling mud system. 
     
     
       8. The system of  claim 1 , wherein the system is an automated system. 
     
     
       9. The system of  claim 8 , wherein the system is a self-contained system. 
     
     
       10. The system of  claim 1 , wherein the first collection tank further comprises at least one separation device. 
     
     
       11. The system of  claim 1 , wherein the second collection tank further comprises at least one separation device. 
     
     
       12. The system of  claim 1 , further comprising a progressive cavity injection pump in fluid communication with the injection pump and the outlet of the primary separation tank, the progressive cavity injection pump configured to disperse a polymer into the drilling waste. 
     
     
       13. The system of  claim 1 , wherein an upper portion of the clarifying tank is fluidly coupled to the first collection tank. 
     
     
       14. The system of  claim 1 , wherein the centrifuge is in fluid communication with a lower portion of the clarifying tank. 
     
     
       15. The system of  claim 1 , wherein the constricted pipe is disposed substantially perpendicular to the internal pipe. 
     
     
       16. The system of  claim 15 , wherein the internal pipe is disposed substantially vertically within the clarifying tank. 
     
     
       17. The system of  claim 1 , wherein the constricted pipe provides turbulent flow. 
     
     
       18. The system of  claim 2 , wherein a feed line separates the tank of the sand trap and the clarifying tank.